I entered the maw in Sauromuge Champaign and began the quest Cavernous Maw, received the white feather, and am now on the quest Back to the beginning. When I was transported to the past, I aggroed a goblin and died without touching another maw. I've been to the three main maws (Sauromunge, Rolanberry, and Batilla) but am not able to get back into any of them.

How do I get back to the past when no maws are active? I really want to unlock dnc.